Temperature
6131 K
6110.0 to 6409
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Stellar HostProfile
Kepler-21
F6 IV • 108.5 pc
Records
21
literature rows
Planets
1
system count
References
22
distinct source labels
HD: HD 179070HIP: HIP 94112TIC: TIC 121214185
Approximate color
from effective temperature
Canonical Summary
Adopted host values from one source row
Values come from the row with the most populated summary measurements. Missing values stay missing. Ranges and counts describe all source rows.
Stellar source: Howell et al. 2012 • System source: TICv8
Mass
1.34 Msun
1.16 to 1.41
Radius
1.86 Rsun
1.11 to 2.04
Age
2.84 Gyr
2.82 to 4.40
Distance
108.5 pc
single adopted value
Spectral Type
F6 IV
Multiple classifications reported
Planets
1
Stable across source rows
Scale Comparison
Radius against the Sun
Current adopted radius: 1.86 R☉ (circles scaled linearly by radius)
Sun
1.0 R☉ baseline
Kepler-21
1.86 R☉
System Layout
Known planets
1 planets linked to this host
Kepler-21 b
Transit
◌
Discovery
2012
Period
2.79 days
Radius
1.64 R⊕
Mass
7.50 M⊕
Eq. Temp
2015 K
Kepler-21 and Its Super-Earth
Kepler-21 is an F6 IV star located 354 light-years from Earth. It is 2.84 billion years old and has a mass of 1.34 solar masses, a radius of 1.86 solar radii, and a temperature of 6130 K. Its reported mass and radius estimates are larger than the Sun's, and it is hotter than the Sun. One planet orbits this host.
Kepler-21 b is a Super-Earth discovered by transit in 2012. A transit occurs when a planet passes in front of its star from our viewpoint, producing a small dip in brightness; repeated dips help establish orbital periods. Kepler-21 b completes an orbit every 2.79 days, has a radius of 1.64 Earth radii, and a mass of 7.5 Earth masses. Both its radius and mass estimates are larger than Earth's, and its mean density is 9.39 g/cm³, 1.7 times Earth's.
Provenance
Underlying measurements and references
Evidence Summary
Rows
21
Stellar refs
21
System refs
1
Distancestable
Parallaxstable
Temperaturedisputed
Massdisputed
Radiusdisputed
Agedisputed
Luminositydisputed
Surface Gravitydisputed
Metallicitydisputed
Spectral Typedisputed
| ST TEFF | ST MASS | ST RAD | ST AGE | ST LUM | ST SPECTYPE | SY DIST | Stellar Ref | System Ref |
|---|---|---|---|---|---|---|---|---|
| 6202 | 1.25 | 1.94 | 3.98 | — | — | 108.5 | Fulton & Petigura 2018 | TICv8 |
| 6131 | 1.34 | 1.86 | — | — | — | 108.5 | Q1-Q17 DR24 KOI Table | TICv8 |
| 6131 | — | 2.04 | — | — | — | 108.5 | Q1-Q6 KOI Table | TICv8 |
| 6131 | 1.34 | 1.86 | — | — | — | 108.5 | Q1-Q16 KOI Table | TICv8 |
| 6131 | — | 2.04 | — | — | — | 108.5 | Batalha et al. 2013 | TICv8 |
| 6131 | 1.34 | 1.86 | 2.84 | — | F6 IV | 108.5 | Howell et al. 2012 | TICv8 |
| 6305 | 1.41 | 1.90 | 3.03 | 0.71 | — | 108.5 | López-Morales et al. 2016 | TICv8 |
| — | 1.33 | 1.89 | 4.40 | — | — | 108.5 | Chaplin et al. 2014 | TICv8 |
| — | — | — | — | — | — | 108.5 | Nordstrom et al. 2004 | TICv8 |
| — | — | — | — | — | G0 | 108.5 | Cannon & Pickering 1918 | TICv8 |
| 6110.0 | — | 1.97 | — | 0.69 | — | 108.5 | Gaia DR2 | TICv8 |
| 6409 | 1.17 | 1.11 | — | — | — | 108.5 | Mortier et al. 2013 | TICv8 |
| 6131 | 1.36 | 2.04 | 3.35 | — | — | 108.5 | Q1-Q8 KOI Table | TICv8 |
| 6248.4 | 1.21 | 1.91 | — | 0.70 | — | 108.5 | TICv8 | TICv8 |
| 6131 | 1.34 | 1.86 | — | — | — | 108.5 | Q1-Q12 KOI Table | TICv8 |
| 6202 | 1.16 | 1.73 | — | — | — | 108.5 | Q1-Q17 DR25 KOI Table | TICv8 |
| 6269 | 1.37 | 1.86 | 2.82 | — | — | 108.5 | Sousa et al. 2015 | TICv8 |
| 6202 | — | 1.95 | — | — | — | 108.5 | Berger et al. 2018 | TICv8 |
| 6162 | 1.24 | 1.79 | 3.55 | — | — | 108.5 | Morton et al. 2016 | TICv8 |
| 6305 | 1.41 | 1.90 | 2.84 | — | — | 108.5 | Bonomo et al. 2023 | TICv8 |
| — | — | — | — | — | — | 108.5 | Q1-Q17 DR25 Supplemental KOI Table | TICv8 |